A demodulation threshold self-calibration method and circuit

Abstract

The invention discloses a demodulation threshold self-calibration method and circuit. The demodulation threshold self-calibration method comprises the steps that firstly, a data receiving module compares a wireless transmission signal with a voltage threshold, corresponding clock signals and data signals are analyzed out, a time calibration module and a carrier time-out sign generation circuit module lock the timing sequence relation of the clock signals and the data signals by utilizing obtainable effective information, and a digital control module decodes the clock signals and the data signals analyzed out by the data receiving module according to a protocol; if an error correcting mechanism of the digital control module continuously analyzes out a wrong data stream in the decoding process, decoding is stopped, a new set of calibration codes are generated according to the algorithm to adjust the threshold, and decoding is carried out again after the timing sequence relation of the clock signals and the data signals is relocked; the steps are carried out repeatedly until the error correcting mechanism does not report errors, and the demodulation threshold self-calibration is achieved. The demodulation threshold self-calibration method and circuit can rapidly achieve self-adaption of a chip, and is simple in design, easy to achieve and low in cost.

Description

technical field [0001] The invention belongs to the field of chip technology, and in particular relates to a demodulation threshold self-calibration method and circuit. Background technique [0002] In wireless signal transmission applications, amplitude modulation (ASK) technology has been widely used. During ASK demodulation, in order to adapt to changes in chip technology, source distance and application environment, it is necessary to automatically adjust the voltage comparison threshold to a suitable position between the two amplitudes. Usually, the demodulation threshold self-calibration adopts the program control method, that is: the threshold can be generated by the configuration of the selection circuit; the configuration data is stored in a programmable non-volatile memory such as EEPROM (electrically erasable programmable read-only memory) or FLASH (flash memory) and initialized by empirical data; if a predefined error condition is established during decoding, th...

AI Technical Summary

Problems solved by technology

[0003] The demodulation threshold self-calibration method of the program control method requires a special EEPROM or FLASH and programming circuit, a more complex special control circuit and algorithm logic, a large number of tests in advance to determine the transfer relationship between configuration data, etc., so the design is difficult. Complicated implementation, high cost, and time-consuming self-calibration

Moreover, both EEPROM and FLASH have a certain lifespan, and there is a possibility of failure, so they are not suitable for applications that require a very high service life, such as human implanted electronic medical devices, etc.

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